The AK-1000 — which will be the world’s largest turbine when it is commercially rolled out — is expected to be capable of producing 1MW in waters that flow at 2.6m/sec.

Mike Smith, chief operating officer at Atlantis, said the Carbon Trust fund will help develop an improved version of the AK-1000 into a full-scale prototype. The improved version, he said, will be fitted with a low-RPM permanent magnet generator that does not require a gearbox.

Smith said the first version of the AK-1000, which has a high RPM permanent magnet generator and gearbox, will be evaluated this summer at the European Marine Energy Centre in the waters off Scotland’s Orkney Islands. The second version of the AK-1000 will be evaluated there for a year starting in 2011.

Unlike other tidal-turbine designs, Smith said the AK-1000’s blades are fixed pitch and therefore do not require pitch control. Also, he said, the turbine does not turn.

Smith explained: ’That’s why it has two sets of blades. The incoming tide drives the first set of blades and the outgoing tide drives the back set of blades.’

He added that when the second version of the turbine is unveiled in 2011, it will effectively only have one moving part — namely the shaft that runs through the centre of the structure.

Smith said Atlantis hopes to deploy its first commercial turbine array in 2013.

Your wrote “The world’s largest operational tidal turbine, rated at 1MW” and then wrote “The AK-1000 — which will be the world’s largest turbine when it is commercially rolled out ” – i.e. it is does not yet exist so it could not be “operational”.

In contrast, SeaGen, Marine Current Turbine Ltd’s technology really does exist and is rated at 1.2MW at 2.4m/s (higher power at a lower rated velocity). It has been installed since May 2008 in Strangford Narrows Northern Ireland and regularly runs at full power (see http://www.marineturbines.com). So far it has operated for more than 1000 hours and delivered over 800MWh into the grid. OFGEM could vouch for this.

So, in short, this Atlantis project you reported is neither the most powerful tidal turbine and nor is it yet operational. Let’s have facts rather than PR aspirations reported by a reputable publication such as yours!